Malicious PDF — malware analysis report

Static analysis result for SHA-256 1b14b611d25b14e7…

MALICIOUS

PDF

9.4 KB
MD5: aaad5ad3da8d344b3d0cfd69719cffaf SHA-1: 228a2b6804d6a78bd9119cc2993ede00bcc21bfa SHA-256: 1b14b611d25b14e7420e450f5f47d30b843f81a170b4db2b2e5aac73e75b9f26
178 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.002 Malicious File

The file is a PDF containing embedded JavaScript, which is known to be a vector for exploitation. Specifically, the 'CVE_2007_5659' heuristic firing indicates the use of the Collab.collectEmailInfo method, a known vulnerability. The embedded JavaScript streams, particularly 'legacy_pdfkit_stage_000.js', are heavily obfuscated but likely contain code to download and execute a second-stage payload. The ClamAV detection further confirms its malicious nature.

Heuristics 6

  • Collab.collectEmailInfo — CVE-2007-5659 critical CVE exact CVE_2007_5659
    PDF JavaScript calls Collab.collectEmailInfo — CVE-2007-5659 is a buffer overflow in Adobe Reader triggered by a long argument or heap-sprayed message field passed to Collab.collectEmailInfo(). Part of a series of Acrobat JS API exploits. (identified after JavaScript deobfuscation)
  • ClamAV: Pdf.Exploit.Agent-35905 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Agent-35905
  • unescape() call high PDF_UNESCAPE
    unescape() found — often used to decode shellcode in PDF JS exploits (matched inside decoded stream)
  • JavaScript action low PDF_JAVASCRIPT
    PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Suspicious extracted artifact info EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0007_000.js
d8a6b4ad1abf04d0c4a4f89535cfb57f7312edef25c443f4e844c8ec9d0929dd
pdf-javascript-stream PDF /JS object 7 at offset 0x19B 352 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s).
legacy_pdfkit_stage_000.js
95b36b1bd03d2dca97bf663511566e143907c4a042cfeec4122a90d812a95da5
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2FE 11928 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 2 eval/decoder/string-building token(s). Carved artifact contains 1 long base64-like blob(s).
legacy_pdfkit_stage_001.js
d773bffc6763b049c9bd52d0add19469619d510287767e5b468e009e74dea858
deobfuscated-js repeated-marker hex decoded JavaScript at offset 0x2FE 5014 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).